trait Cook{
    fn start(&self);
} 

trait Wash{
    fn start(&self);
}

struct Chef;

impl Cook for Chef{
    fn start(&self){
        println!("cook start");
    }
}

impl Wash for Chef{
    fn start(&self){
        println!("Wash start");
    }
}

fn main(){
    let chef = Chef;
    Cook::start(&chef);
    Wash::start(&chef);
    <dyn Cook>::start(&chef);
}
